With the advancement in technology, various types of light emitting elements having low power consumption and high luminous efficiency are developed. Among others, light-emitting diode (LED) has relatively low power consumption and relatively high light efficiency, and therefore has gradually replaced the cold cathode fluorescent lamp (CCFL) and other existing illuminating light sources. However, heat produced by the light-emitting diode during operation thereof is still a problem to be solved. A proper heat radiating design would increase the luminous power and service life the light-emitting diode. Therefore, the successful development of light-emitting diode lies in the effective radiation of heat produced by the LED during operation thereof.
In conventional high-power light-emitting diodes, for the purpose of heat radiation, the chip is fixedly mounted on a heat radiating element or strip and electrically connected to a lead frame via conductive leads. Heat produced by the chip during operation thereof is directly radiated and dissipated via the heat radiating element or strip. However, the heat radiating element or strip is additionally provided to inevitably increase the material and assembling costs of the light-emitting diode. And, due to limited available space, the heat radiating element or strip generally has insufficient radiating area and efficiency to satisfy the requirement of radiating heat over a long period of time. Therefore, there is accumulated heat having adverse influence on the luminous efficiency and service life of the conventional light-emitting diodes.
It is therefore tried by the inventor to develop an improved light-emitting diode packaging structure to eliminate drawbacks existed in the conventional light-emitting diode packaging structures.